Too many opinions and not enough substance. #6 and #11 are purely subjective. Be careful with #3. While technically true by the letter of the law, if you add an intake and you have a blown headgasket or something, you can be assured that the repair won't be warranteed.
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Current Rides: 2007 BMW 335i Sedan 6MT Montego Blue, 2004 Subaru Impreza WRX STi (for sale), 2004 Mazda RX-8 6MT
Fondly Remember: 1988 Porsche 924S, 1992 Mitsu 3000GT SL, 2001 BMW Z3 2.5i